Treatment of materials



Patented May 1934i 1,957,494 TREATMENT or MATERIALS George Holland Ellis, Spondon, near Derby, England, assignor to Celanese (Corporation of America, a corporation of Delaware No Drawing. Application October 28,

Serial No. 571,690. In Great Britain December 12 Claims.

areas;'as an alternative, the material may first be printed with the discharge composition and then coloured with the ground colour, the printed area's remaining uncoloured. In both cases a dyestufi having an afiinity for the material or capable of being fixed thereon, and which is 1 in the discharge composition when coloured pattern effects upon a coloured ground may be obtained.

It is customary, after application of the discharge composition, to submit the materials to steaming or ageing or equivalent treatment in order to effect or complete the action of the discharging agent and also to fix properly colouring matter in the discharge preparation and/or the ground colour. In general a short steaming only is necessary to cause the discharging agent to act but a relatively much longer steaming for the fixation of the colour on the material. During the subsequent'lengthy steam or equivalent after-treatment to fix the colour on the material there is a tendency for the discharging agent to suiluse into areas outside the printed areas so that the printed areas .become surrounded by halos" or rings where the ground colour has, become partially discharged or modified in shade, Such eilects are especially liable to occur on materials made of -or containing organic derivatives of cellulose as a somewhat prolonged steaming is in general necessary in producing pattern effects on these materials.

In producing discharge effects, particularly coloured discharge effects, upon textile materials in accordance with the present invention the foregoing defects due to suil'usion of the discharging agent' during steaming or equivalent after-treatment are avoided by counteracting the residual excess of discharging agent after discharge of the ground colour and before any relatively lengthy ageing, steaming or like aftertreatment requisite for the fixation of colouring .rnatters applied in admixture with the discharging agent and/or for the purpose of ground eolouration.

This counteraction, which further serves to prevent destruction of the illuminating colour during steaming or the like, is conveniently achieved by treating the material with a reagent opposite in character to the discharging agent; thus for example in the case of a reduction discharge the material may be treated with an oxidizing agent, or in the case of an oxidation dischargewith a reducing agent.

The agents adapted to counteract the discharging agents may, after discharge of the ground colour, be applied to the materials in any convenient manner, for example in the form of aqueous solutions by padding. Thus a textile fabric may be uniformly coloured, then printed with a composition containing a reducing discharging agcnt and a dyestuil resistant thereto and having an aifinity for the fabric, dried, aged, or steamed for a short time to eflect the dis charge of the ground colour in the printed areas, then padded with a solution of an oxidizing agent, and finally subjected to steaming to fix on the material the dyestufi present in the dis-- charge composition.

Examples of oxidizing agents suitable for counteracting excess of reducing discharging agents in accordance with the process of the present invention are bichromates, per-sulphates, and perborates. When employing acid reducing discharging agents such for example as stannous salts e. g. 'stannous chloride, it is of further advantage to incorporate an alkali with the oxidizing agent or to use an alkaline oxidizing agent. A very eii'ective alkaline oxidizing agent is an alkali metal perborate.

The following examples illustrate in more detail the process according to the present invention, but it should be understood that these examples are given by way of illustration only and are in notway limltative:--

Example I and developing with betaoxynaphthcic acid, is printed with a paste of the following composition:

' i a Grains 1 amino 2 methyl anthraquinone Y milled aqueous paste 100 Methylated spirits; 100 Gum arabic 1:1 500 Potassium sulphocyanide Citric acid "a 10 Water "a 115 Stannous chloride 150 After drying and ageing the goods for ashort time to effect the discharge of the ground colour they are padded with a 1% solution of sodium perborate, dried and steamed for to 40 minutes A woven fabric of cellulose acetate yarn is dyed according to known methods with 1% of Malachite green crystals colour index No: 657. The fabric is then dried and prepared for printing as usual. 1

By means of the usual type of two-colour printing machine, the following .two printing pastes are applied:

' Grams (2' Dark British gum 30% Citric acid Sodium chlorate Caustic soda; 22.5 I Potassium ferricyanide 20.0

1 amino Z-methyI-anthraqninone (20% aqueous paste) 150.0

. W Grams (ii) Dark British gum 30% 537.5 Citric acid": 120.0 Sodium chlorate 150.0 Caustic soda. 22.5 Potassium ferricyanide l 20.0 1 acetyl amino anthraquinone (20% aqueous paste) 150.0

After printing, the fabric is dried and aged for 5-8 minutes in the continuous Matther 81 Platt ager. It is then padded in a 2% solution of sodium bisulphite, dried and steamed hour either in a cottage steamer or continuous ape,

paratus.

There results a yellow and orange two-colour discharge ona green groundfthe impression becellulose acetate, cellulose formate, cellulose propionate and cellulose butyrate or ethers of cellulose'such as methyl cellulose, ethyl cellulose and benzyl cellulose. The invetnion is, however valuable also for the production of pattern effects on mixed materials containing cellulose derivatives and'bther textile fibres, e. g. cotton, regenerated cellulose, silk, wool, or other textile fibres, or on materials containing these fibres and no cellulose derivative.

What I claim "and desire to secure by Letters Patent is: 1

a 1. Process for the production of coloured discharge eflects on textile'materials comprising an organic derivative of cellulose, comprising applying thereto a discharging agent in admixture with a colouring matter resistant thereto, ageing to effect discharge, rendering ineffective the excess discharging agent,'and thereafter steaming to effect fixation of the resistant colouring matter.

2. Process for the production of coloured discharge effects on textile materials comprising cellulose acetate, comprising applying thereto a discharging agent in admixture with a colouring matter resistant thereto, ageing to efiect discharge, rendering ineffective the excess discharging agent, and thereafter steaming to effect fixation of the resistant colouring matter.

3. 1n the production of pattern effects on textile materials by processes involving the application of reducing discharging agents followed by steaming to fix colouring matters present on said textile materials, rendering the residual discharging agent inefi'ective by means of an oxidizing agent after effecting the discharge but prior to at least part of the after-treatment.

4.In the production of pattern effects on textile materials comprising an organic derivative of cellulose by processes involving the application of reducing discharging agents followed by steaming to fix colouring matters present on said textile-materials, rendering the residual discharging agent ineffective by means of an oxidizing agent after effecting discharge but prior to at least part of -the after-treatment.

5. In the production of pattern effects on textile materials comprising cellulose acetate by processes involving the application of reducing discharging agents followed bysteaming to fix colouring matters present on said textile materials, rendering the residual discharging agent ineffective by means of an oxidizing agent after effecting discharge but prior to at least part of the after-treatment.

6. In the production of pattern effects on textile materials comprising an organic derivativ of cellulose by processes involving the application of reducing discharging agents followed by steaming toflx colouring matters present on said textile materials, rendering the residual discharging agent inefiective by means of an oxidizing agent selected from the group consisting of chromates, persulphates and perborates after efiecting discharge but prior to at least part of the steaming.

'7. In the production of pattern effects on textile materials comprising cellulose acetate by processes involving the application of reducing discharging agents followed by steaming to fix colouring matters presentron said textile materials, rendering the residual discharging agent ineffective by means of an oxidizing agent selected from the group consisting of chromates,

persulphates and perborates after effecting discosmos charge but prior to at lenst port of the steaming.

8. Process to; the production oi coloured oischecge effects on textile meteriels comprising an organic derivative oi cellulose, comprising epplying thereto .25 disches ing agent in admixture o colouring matter resistant thereto, ageing to eitect s'iischerge, epplying to the materials by on egent ocieptetl to render the excess discharging egent ineffective, and thereafter steaming to efiect fixation of the colouring metplicetion of discharging agents followed by steaming to fix colouring matters present on seid textile materials, rendering ineffective the residuel discharging agent otter eiiecting oiscfoorge but prior to at least part of such ii. in the production of pattern eifects on textfie materials comprising an organicderivative of cellulose Toy processes involving the application of discharging agents followed by steam.-

ing to for coloring matters present on said text tile materials, rendering inefiective the residual discharging agent after efifecting discharge but prior to at least part of such steaming.

' 12. In the production oftpattern effects on textile materials comprising cellulose acetate by processes involving the application of discherg= ing agents followed by steaming to fix coloring matters present on said textile materials, rendering inefiective the residual discharging agent after effecting discharge but prior to at leest part of such steaming.

GEORGE HOLIJAND ELLIS. 

